Portable electronic devices, such as electronic book (e-book) readers or tablet computers, have become increasingly popular. Due to the time required to read lengthy novels or other types of e-books, lightweight e-book readers are desirable in order to promote reading for hours at a time. One constraint on usability for portable electronic devices is their durability to withstand accidental falls of the devices and accidental impacts of objects onto the devices. However, increasing the durability of electronic devices typically has the undesirable effect of increasing the weight of the devices due to the increased structural strengthening. Accordingly, there is a need for improved electronic devices with adequate durability to withstand device stress testing while minimizing overall device weight.